Inventor HSM supports Axial offset passes that allow you to repeat the calculated toolpath in steps in the Z direction.
Axial offset passes work much like multiple finishing stepdowns in the 2D operations and are useful for removing a fixed amount of stock in several steps. As an example, if you have 1 mm of stock left you can remove this in five passes of 0.2 mm using parallel finishing.
Axial offset passes settings
Without axial offset passes
With three axial offset passes